Relationship between IgA nephropathy and Histocompatibility Antigens (HLA) in Korean Population

Shin, Young Shin; Kim, Young Ok; Park, Chul Whee; Yoon, Sung No; Yang, Chul Woo; Kim, Yong Soo; Chang, Yoon Sik; Han, Hoon; Bang, Byung Kee

Abstract

OBJECTIVES
Primary IgA nephropathy(IgAN), currently recognized as the most prevalent form of glomerular disease in the world, has tendency toward end stage renal failure at a rate of 20-30% in patients after a long-term follow-up of more than 20 years. But its etiology and pathophysiology is not fully understood. This study was designed to evaluate the pattern of histocompatibility antigens(HLA) and its association with poor prognostic factors in patients with IgAN.
METHODS
Study population comprised the 69 patients with IgAN which was diagnosed by clinical and pathological findings, and control groups were 202 healthy Korean people. We evaluated the HLA class I serologic typing by standard microlymphocytotoxic technique and the HLA class II genotypes by the two-step polymerase chain reaction.
RESULTS
1. HLA-A was not associated with IgAN. 2. The phenotype frequency of HLA-B55 was 6.1% in patient group and 1.7% in normal control group. HLAB55 was associated with IgAN(relative risk 3.47, P<0.05). 3. HLA-DQB1*04 was also associated with IgAN (relative risk 3.57, P<0.05). 4. There was no significant difference in the distribution of HLA in IgAN patients according to histologic grading, blood pressure, renal function and proteinuria.
CONCLUSIONS
Frequencies of HLA-B55, HLA-DQB1 *04 are higher in Korean patients with IgAN compared to general population. But we could not observe the significant relationships between HLA type and poor prognostic factors. Further study using larger population with IgAN may be necessary to identify the association of HLA locus with poor prognostic factors and progress decline in renal function in patients with IgAN.